1. Field of the Invention
This invention relates to systems for minimizing damage to an automobile and injury to its occupants in a frontal collision, and more particularly concerns automotive vehicles having front energy-absorbing means and a movable passenger compartment.
2. Description of the Prior Art
U.S. Pat. Nos. 3,508,783; 3,695,629; 3,589,466; 5,738,373; 3,806,184; 3,743,347 and 3,479,080 describe passenger compartments which, upon frontal impact, slide forwardly and upwardly. Such movement protects the occupant from injury by providing a longer effective stopping distance and causing the occupant""s body to assume a semisupine position which can more effectively cope with impact force. None of these patents, however, provide means for making the vehicle itself particularly less damageable.
U.S. Pat. No. 3,848,886 describes an impact-absorbing frame system with telescoping bumper mounts and a frame equipped with energy absorbing sections which collapse on impact. Again, this does not make the vehicle itself particularly less damageable.
U.S. Pat. No. 4,232,755 describes an electric motor vehicle divisible into separable front, middle and rear sections. The middle section includes a passenger compartment that slides fore and aft in a collision. However, the compartment does not tilt the passenger to a protective semisupine position. Aside from the telescoping bumper mounts it has no further means for minimizing collision damage.
U.S. Pat. No. 3,476,434 describes an automotive vehicle having a shock mounted passenger-carrying area which is free to move horizontally, whereby deceleration forces on the passengers are dissipated more slowly. It has no means for making the vehicle less damageable.
U.S. Pat. No. 3,560,041 describes a driver/passenger compartment mounted on a separate chassis, with shock-absorbing means between them. It describes extensive interior padding to protect the occupants from head to foot but has no means for making the vehicle less damageable.
U.S. Pat. Nos. 5,941,582; 5,884,959 and 4,441,751 describe various means for improving the impact-absorbing capacity of front bumper assemblies. The impact force of the collision is thus ultimately transmitted to the frame. There are no provisions for making the frame itself less prone to damage from this force.
U.S. Pat. No. 5,451,077 describes a resilient safety bumper and a two-piece frame. The bumper partially absorbs the impact, and the front section of the frame swivels sideways to further protect the passenger-carrying rear section from impact shock. It has no means for making the vehicle as a whole less damageable.
In U.S. Pat. Nos. 4,192,538; 4,411,462; 4,518,183 and 4,176,858, the bumper assembly utilizes an air container means such as an air bag to improve its impact-absorbing capacity. The bumper assembly is mounted to the adjacent portion of the vehicular frame, to which the impact force of the collision, albeit dampened, is ultimately transmitted. They do not include means for making the frame itself less deformable or less damageable.
U.S. Pat. No. 4,065,169 describes an energy transforming means which allows an upward movement of a truck""s rear body, exclusive of the passenger compartment, to absorb kinetic energy of the body upon collision. It does not describe a separate passenger compartment slidably mounted on the chassis and does not describe means for making the vehicle less damageable.
It is evident from the above that although many patents address the problem of passenger safety and address the matter of improving the impact-absorbing capacity of the bumper assembly, none of them present means for making the vehicle itself less damageable, particularly its frame or chassis. It is well known that a bent frame or chassis is frequently the reason for declaring the vehicle a total loss.
It is accordingly the primary object of this invention to provide a vehicle that is not only safer for its occupants during a frontal collision but also one that is less damageable. It achieves this by a novel approach based on the observation that a hollow body in motion such as an automobile whose structural integrity is maintained by a deformable framework is more apt to sustain damage and deformity if its motion is halted by a compressive force applied to its leading aspect (xe2x80x9ca push from the frontxe2x80x9d) than if its motion is stopped by an equal traction force acting on its rear aspect (xe2x80x9ca pull from behindxe2x80x9d). This is because in general the materials used in automobiles such as the chassis is more apt to be bent when pushed from the front end than when pulled (to a stop) from the rear end, other factors being equal. That is, they are better able to withstand tensile stress than compressive or bending stress.
The novel approach used in this invention is the means for instantaneous transfer of the impact force from the front bumper to the rear bumper, making it possible to use the rear bumper as a strong anchor from which to exert a strong controlled traction force (xe2x80x9cpull from behindxe2x80x9d) on the chassis and thereby gradually pull the chassis and the rest of the vehicle to a controlled stop.
Another purpose of this invention is to reduce the cost of manufacture by using standard off-the-shelf parts such as the illustrated leaf springs and shock absorbers, and straight tubular members for the chassis and bumper supports which are not only inexpensive to fabricate but are also less apt to be deformed when subjected to strong axially directed forces like those that occur during frontal collisions.